[third_party] add polymer 1.2.3

polymer_1.2.3/bower_components/iron-menu-behavior/bower.json

 {
   "name": "iron-menu-behavior",
-  "version": "1.0.1",
+  "version": "1.0.7",
   "description": "Provides accessible menu behavior",
   "authors": "The Polymer Authors",
   "keywords": [
     "web-components",
     "polymer",
     "behavior",
     "menu"
   ],
-  "main": "iron-menu-behavior.html",
+  "main": [
+    "iron-menu-behavior.html",
+    "iron-menubar-behavior.html"
+  ],
   "private": true,
   "repository": {
     "type": "git",
     "url": "git://github.com/PolymerElements/iron-menu-behavior"
   },
   "license": "http://polymer.github.io/LICENSE.txt",
   "homepage": "https://github.com/PolymerElements/iron-menu-behavior",
   "ignore": [],
   "dependencies": {
     "iron-selector": "PolymerElements/iron-selector#^1.0.0",
     "polymer": "Polymer/polymer#^1.0.0",
     "iron-a11y-keys-behavior": "polymerelements/iron-a11y-keys-behavior#^1.0.0"
   },
   "devDependencies": {
+    "paper-styles": "polymerelements/paper-styles#^1.0.2",
     "iron-component-page": "PolymerElements/iron-component-page#^1.0.0",
+    "iron-test-helpers": "polymerelements/iron-test-helpers#^1.0.0",
     "test-fixture": "PolymerElements/test-fixture#^1.0.0",
-    "web-component-tester": "*",
+    "web-component-tester": "polymer/web-component-tester#^3.4.0",
     "webcomponentsjs": "webcomponents/webcomponentsjs#^0.7.0"
   }
 }